The California Second District Court of Appeal denied the petition by Samantha Geimer without comment.
Geimer's attorney petitioned the court on March 23 to dismiss the case against Polanski, arguing recent changes to California's constitution gave her more rights as a victim to influence the case.
"She is a person who is harmed by the maintenance of the prosecution and she wants it to end," Geimer's attorney wrote in the petition for dismissal. "She has not been treated fairly."
Prosecutors argued in a filing last week that voters' decision in 2008 to include a victim's bill of rights in the state's constitution didn't grant Geimer or other crime victims the authority to end prosecutions.
Thursday's ruling is unlikely to have any immediate bearing on Polanski's status. The Oscar-winning director remains on house arrest at his chalet in the Swiss resort of Gstaad.
The appeals court has not yet ruled on another petition his attorneys filed earlier this year, records show.
A message left for Geimer's attorney, Lawrence Silver, was not immediately returned Thursday. Sandi Gibbons, a district attorney's spokeswoman, said Thursday she had not yet seen the dismissal and could not comment.
Polanski was accused in 1977 of plying Geimer, then age 13, with champagne and part of a Quaalude pill, then raping her at Jack Nicholson's house.
Polanski was indicted on six felony counts, including rape by use of drugs, child molesting and sodomy. He later pleaded guilty to one count of unlawful sexual intercourse.
Authorities are seeking Polanski's extradition from Switzerland so he can be sentenced on the charge. The Academy Award-winning director fled the United States on the eve of sentencing in 1978.
Polanski's attorneys have argued that there was substantial misconduct by the judge in that case, who is now deceased, and filed new evidence supporting the claim in their active appeal.
Geimer's petition also sought the release of secret testimony by the former prosecutor handling Polanski's case, who at the time expressed concerns about misconduct about the judge. Transcripts of his recent closed-court testimony remain sealed and unavailable for public review.
